#include<bits/stdc++.h>
#define all(a) a.begin(), a.end()
using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
using vi32 = std::vector<int>;
using pii32 = std::pair<int, int>;
using vii32 = std::vector<pii32>;
using vi64 = std::vector<i64>;
using pii64 = std::pair<i64, i64>;
using vii64 = std::vector<pii64>;

//std::mt19937 rng {std::chrono::steady_clock::now().time_since_epoch().count()};




int main(){
	std::ios::sync_with_stdio(false);
	std::cin.tie(0);

	int l, r;
	std::cin >> l >> r;
	int cnt = (l == 1 ? 1 : 0) + (r == 1 ? 1 : 0);
	if(cnt == 1) {
		std::cout << "Yes\n";
	} else {
		std::cout << "Invalid\n";
	}

	
	return 0;
}